Electric space heaters, because of their safety and convenience, are a popular means of heating commercial and residential living space. One type of electric space heater recently introduced into the market is the electrical thermal storage (ETS) heating unit. ETS heating units are particularly useful when the cost of electricity varies during the day (off-peak rates) because they can generate and store heat when the cost of electricity is low and use the stored, low-cost heat when the cost of electricity is high.
Typical ETS heaters include a heat sink surrounded by an insulated housing; at least one duct through the heat sink and housing for allowing surrounding air to be circulated past and heated by the heat sink; an electric heating element within the housing for generating heat; a fan for circulating air through the ducts; a thermostat for measuring the temperature of the space to be heated and controlling operation of the fan accordingly; and a thermostat for measuring the temperature of the heat sink and controlling the amount of heat stored in the heat sink by controlling operation of the heating element. While the heating unit requires a thermostat to measure room temperature in order to properly control the operation of the fan, these thermostats are typically not supplied by the manufacturer but are readily available to the consumer at many retail outlets.
Normal wear and tear of typical ETS heaters requires that the heating elements be periodically replaced. Unfortunately, the heating elements in typical ETS heaters are placed within the heat sink and the housing such that in order to replace the heating elements it is necessary to remove a portion of the housing, a portion of the insulation, and all or a portion of the heat sink; making the repair of worn heating elements in typical ETS heaters difficult and time consuming. Further, each time the insulation is disturbed in order to repair the heating elements the integrity of the insulation is destroyed and its insulating value decreased.
Accordingly, a need exists for an ETS heater designed to allow worn heating elements to be quickly and easily replaced without adversely affecting the integrity of the insulation.